U.S. Reps. Bennie Thompson of Mississippi, Sheila Jackson Lee of Texas and Yvette Clarke of New York say in a letter to the MTA's chairman that the workers are "an important link in the transit security chain.''

An MTA spokesman says subway safety will not suffer given the strong police presence. The agency says the cut backs will save $50 million.

The workers staff customer service booths at some subway entrances -- and without them, the congressional representatives claim, the stations will be more vulnerable to attack.

"Although our domestic transit systems have thus far been spared," they wrote, "deadly terrorist attacks in Spain, Great Britain, India and Russia over the last few years have emphasized the vulnerabilities of public transportation in large urban areas and demonstrated the security challenges unique to these open, passenger-heavy systems."